PARIS (AFP) - Air traffic controllers in France were poised to go on strike Wednesday, likely leading to cancellation of some 40 per cent of flights in French airspace.

"Disruption is expected over the whole country," said the DGAC civil aviation authority, which requested companies to scrap 40 per cent of flights as a preventative measure.

The main air traffic controllers' union, the SNCTA, has also urged industrial action on April 16-18 and April 29 to May 2.

They are calling for talks over working practices and retirement age, currently set at 59 for air traffic controllers.

The SNCTA union had originally threatened to go on strike earlier but scrapped the industrial action in the wake of the Germanwings crash that killed 150 people.